Variable tuning inductance device



July 2, 1929; w. AULL, JR, ET AL. 78,161

VARIABLE TUNING INDUCTANCE DEVICE Filed Sept. 6, 1922 MQWM MA/M

JNVENTOR B yfim, 3w, wa w A WO'RNEY Patented July 2, 1929.

UE'FEB dTATEd PATENT OFFICE.

WILSON AULL, JR., OF NEW YORK, N. Y., AND HARRY W. HOUCK, OF EAST ORANGE, NEW JERSEY, ASSIGNORS TO RADIO INVENTIONS, INC., OF NEW YORK, N. Y., A.

CORPORATION OF NEW YORK.

VARIABLE TUNING INDUGTANCE DEVICE.

Application filed September tanee or transformer, as the case may be,

which can be easily and quickly operated to effect adjustments corresponding with the wave length of any desired signal.

To these ends the invention contemplates a plurality of adjacently mounted coils of the well known honeycomb or duolateral type enclosed in a suitable container consisting of two circular end platesconnected together by a cylindrical shell. An arcuate row of terminals is mounted on one of the end plates and taps from the several coils are brought out to the fixed terminals.

The inductance units are provided with a common rotatable shaft which extends through their several axes and a plurality of contact arms are secured to and electrically connected to the shaft. Each of these con tact arms is individually connected to one of the inductance units and is arranged to wipe over the fixed contacts thereof when the shaft is rotated.

The inductance unit, per se, and the assemblage comprising a plurality of such units, includes a number of novel features. One of these features resides in the form of construction wherein several coils, preferably of the honeycomb or duolateral type, are each wound on short tubes of fibre or other suitable material and mounted side by side on a longer supporting tube. Another feature resides in the form of construction wherein two end plates are provided each having an annular groove in one of its faces into which one end of the supporting tube is seated and secured by an adhesive such as ordinary glue. A metallic shell, preferably in the form of a cylinder, connects the two end plates together thereby forming a complete enclosure for the coils and supporting tube. The several coils are connected together and taps are brought out from their juncturcs and extremitiesto the fixed contacts on the outside of. one of the end plates. A suitable bracket'mcmber is secured to each of the shells and these are so arranged that they may be connected together serially thereby combining several units into a. complete assemblage.

The invention will be better understood from the following detailed description with 6, 1922. Serial No. 586,422.

Fig. 1 is a view in elevation showing the .assembly of a pair of variable inductance units with a common operating shaft;

Fig. 2 is a longitudinal section through the casing of one of the variable inductance units;

F 1g. 3 is a cross sectional View taken along the line 55 of Fig.. 2; I r

Fig. 4 is an end view of the inductance unit of Fig. 2; and

Fig. 5 is an enlarged longitudinal section taken along the axes of the variable inductance.

In Fig. 1 two inductance units 36 are shown connected together and provided with a common shaft 17 which extends through the axes of the two units.

Each unit consists of a tubular supporting member 37 of vulcanized fibre or other suitable insulating material on which are adjaocntly mounted a plurality of short tubular cores 38 on each of which is wound a coil, preferably of the honeycomb or duolateral type 39, 40, 41, 42,43 and 44. The ends of the tubular supporting member 37 are seated in annular grooves provided on the inner faces of the circular end plates and 46 and a metal shell 47 is supported by the end plates 45 and 46 and forms therewith an enclosure for the coils 39 to 44 inclusive. A number of fixed contacts 48 are mounted in an arcuate row on the end plate 45 and are connected to the extremities and junctures of the coils 39 to 44 inclusive, as is quite clearly shown in Figs. 2 and 5. The shaft 17 carries a plurality of contact arms 49, one for each inductance unit, each of which is adapted to wipe over its respectively associated set of fixed contacts 48. Electrical connections may be taken off from the shaft 17 by way of the binding posts 50. connector 51 and collar 52 which is secured to the shaft 17. A lead from one extremity of the coils is connected to the fixed terminal 53 mounted on the end plate 45.

To each of the shells 47 there is secured a bracket member 53 by means of rivets 54 and these brackets are suitably proportioned as indicated in Fig. 1 for connecting the inductance I ary coils may be readily constructed by mounting an additional coil or coils in a structure similar to that illustrated.

The invention, as embodied in the appara tus, may take a number of alternative forms and is not to be limited except by the scope of the appended claims. i

The multistage tuned radio frequency receiver system as set forth in the original application is claimed broadly in our application #567,184, filed Nov. 5, 1925, as a division hereof, and the system embodying transformer coupling is claimed in our application #278,236, filed May 16, 1928.-

We cla1m:

1. In combination, a plurality of variable inductance devices each comprising a coil supporting member, one or more coils mounted on saidsupporting member, an enclosure for said coil or coils and said supporting member ineluding a pair of end plates, a set of fixed contogether.

tacts on one of said end plates, and conductors connecting sald coil or coils with said contacts,

a shaft extending through and common to said inductance devices, a plurality of contact arms secured to and rotatable with said shaft, each of said contact arms being individually associated with and adapted to wipe over one of said sets of cont-acts, a bracket meniber secured to each of saidinductance devices, said bracket members being arranged to be connected together end to end for supporting said inductance devices in alignment and means for connecting said bracket members 2. In combination, a plurality of variable inductance devices arranged in noninductive relation with respect to each other, and each comprisinga coil supporting member, a number of coils mounted on said supporting member, an enclosure therefor, a set of fixed contacts and conductors connecting said coils with said contacts, an actuator common to said inductance devices, a plurality of contact arms coils mounted on each of said coil supporting means, means for simultaneously and equally varying the inductance of the coils on each of said coil supporting means, said coils being so mounted and connected that the adjustment of the coils on one of said coil supporting means has substantially no inductive coupling elicct on the coils on the other coil supporting means.

4. In combination, a plurality of variable inductance devices each comprising a coil supporting member, a number of coils mounted on said supporting member, an enclosure for each of the set of coils and its supporting member, a bracket member secured to each of said inductance devices, said bracket members being arranged to be connected together in alignment end to end for supporting said inductance devices, means for connecting said bracket members together and a single means for simultaneously and equally varying the inductance of each inductance device.

5. A variable tuning device comprising a plurality of variable inductance devices arranged in noninductive relation with respect toeach'other, and each comprising coil supporting means and a number of coils mounted thereon, and means for simultaneously and equally varying the inductance of each of said inductance devices, the constants of said inductance devices being adapted to inter-tube coupling.

In testimony whereof We afi ix our signatures.

WILSON AULL. .Tu. HARRY W. HOUGK. 

